<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    
</body>
</html>
<script  src="./js/b.js">
</script>
<script  src="./js/a.js">
</script>
 


<script>
    console.log(a_x);
    console.log(b_x);
</script>